The average number of pages Wendy read in a certain number of days was 19. In the next seven days, Wendy read another 13 pages. As a result, the average number of pages she read decreased to 17. How many days did Wendy read in total?
| |
At first |
In the end |
| Number |
1 u |
1 u + 7 |
| Value |
19 |
17 |
| Number x value |
19 u |
17 u + 119 |
Number of days that Wendy read at first = 1 u
Number of pages that Wendy read at first
= 1 u x 19
= 19 u
Number of pages that Wendy read in the end = 19 u + 13
Number of days that Wendy read in the end = 1 u + 7
Number of pages that Wendy read in the end
= 17 x (1 u + 7)
= 17 u + 119
19 u + 13 = 17 u + 119
19 u - 17 u = 119 - 13
2 u = 106
1 u = 106 ÷ 2 = 53
Number of days that Wendy read in the end
= 1 u + 7
= 53 + 7
= 60
Answer(s): 60
